Abstract

In the present work, a novel platform has been designed to fabricate an electrochemical sensor composed of chitosan nanofibers modified with sodium dodecyl sulfate, a negatively charged surfactant, and hemoglobin protein for direct and sensitive determination of hydrogen peroxide. Chitosan nanofibers were synthesized through the electrospinning process and characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The synthesized nanofibers provided a large surface for the adsorption of hemoglobin. Immobilization of hemoglobin on the fibers was investigated by cyclic voltammetry, and the modification steps were followed by electrochemical impedance spectroscopy. Under the optimal conditions, the fabricated biosensor was employed for electrocatalytic determination of hydrogen peroxide by differential pulse voltammetric and amperometric methods in the linear range 3.0-2940.0 mu M (detection limit = 0.16 mu M) and 1.0-201.0 mu M (detection limit = 0.05 mu M), respectively. The applicability of the constructed biosensor was also evaluated by hydrogen peroxide determination in real samples, and satisfactory recoveries were obtained which confirmed that the proposed method provides a simple and sensitive method for the hydrogen peroxide monitoring.